Wuzhi ZK-TB21 Real World Test (with bookshelf speakers and passive sub)
I have modified it semi-successfully to bypass the built in bluetooth chip (which harms the analogue input quality), and now use it for my desktop speakers. I strongly suggest using a fan to blow on the heatsink at high volumes for a long time, the unit gets very toasty after a while and I would hate for it to overheat.
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